The invention herein resides in the art of devices for packing or filling cartons and the like. More particularly, the invention comprises an improvement in apparatus for opening and folding outwardly the flaps of paperboard cases or cartons which, in a filling line, have previously had the flaps folded inwardly.
Heretofore in the art, it has been known to utilize shoes or the like for folding outwardly the side and rearward flaps of a container moving along a conveyor line in a filling system. These flaps have generally been opened with little difficulty in that they have an edge which may be easily accessed by the shoes or other opening apparatus. However, the opening of the front flap has posed serious problems in that the leading edge thereof is attached, at a scoreline, to the container proper. Various attempts have been made to circumvent these problems including the utilization of cam-actuated needles inserted under a side edge of the front flap and arcuately operated to fold the flap outwardly. Air guns or other such devices have been utilized in conjunction with such needles to blow a burst of air into the container with the rebounding air lifting the flap upwardly to make the same more accessible by the needle. Further, suction devices have been known in the art for opening the front flap.
The foregoing prior art has been plagued with numerous drawbacks. The cam-actuated needle, entering under a side edge of the front flap, often times tears or creases the flap, especially when the scoreline of the flap is discontinuous or of varying depth. Further, if the front flap is folded downwardly to a point within the container, the air gun and suction device aforementioned are often times insufficient to retrieve the flap. This problem is even more acute if the carton itself is twisted or cocked such that the front flap binds against a side wall thereof. Yet further, the prior art devices have generally been of a complex nature and not easily adjusted to accommodate various size boxes. Yet further, the prior art has taught the positioning of the front flap opener under the filling head itself, requiring a clearance between the filling head and the container sufficient to allow the front flap to open thereunder, thus necessitating an elevation mechanism associated with the filling station. Yet another drawback of the prior art is the generally large physical size of the front flap openers, taking up an inordinate amount of space at the filling station.